Control method and apparatus for arc discharge



Dec. 30, 1952 L. R. NOFFSINGER 2,624,026

CONTROL METHOD AND APPARATUS FOR ARC DISCHARGE Filed April 17, 1951CONTROL BOX ATI'CI R N EYS Patented Dec. 30, 1952 CONTROL METHOD ANDAPPARATUS FOR ARC DISCHARGE Louis B. Nofisinger, Alexandria, Va.

Application April 17, 1951, Serial No. 221,493

(Granted under the act of March 3, 1883, as amended April 30, 1928; 3'700. G. 757) Claims.

The invention described herein may be manufactured and used by or forthe Government for governmental purposes, without payment to me of anyroyalty thereon.

This invention relates to electrode assemblies for are lamps and thelike generally, and more particularly, to a method and apparatus formaintaining a point of arc discharge in fixed relation between arcingelectrodes.

Various types of electrode assemblies are used in arc lamps and similartypes of equipment to establish a source of light or heat and otheruseful forms of electrical energy. Such electrode assemblies usuallytake the form of spaced consumable electrodes connected in circuitrelation with a suitable source of electrical power and including meansfor feeding the electrodes relative to each other. The prior artsuggests various methods and apparatus for controlling the feed of theindividual electrodes and for indirectly controlling the point ofdischarge of the are between the electrodes in such assemblies.

Methods and apparatus of the latter type operate on the principle ofrecognition of or indirect reaction to are displacement by somesensitive means, such as a visual or thermo-electric element, whichtransforms and relays the effect of such recognition or reaction to asuitable electrode control mechanism. Such elements are usually spacedfrom the are so that the recognition or reaction is indirect with theattendant disadvantages of time lag and lack of sensitivity.

It is an object of this invention to provide a method of maintaining apredetermined relation between arcing electrodes and the position of anarc discharge therebetween in direct response to displacement of the arcdischarge from the predetermined relation.

Another object of this invention is to provide a simple and economicalelectrical control apparatus which responds directly to are displacementby contact therewith to maintain a fixed relation between the positionof are discharge and .arcing electrodes.

A further object of this invention is to provide a method of controllingmovement of an arcing electrode in direct response to arc displacementto maintain the position of arc discharge in fixed relation between thearcing electrodes.

Briefly, in accordance with this invention, there is provided amethodand apparatus for maintaining a fixed relationship between movableelectrodes and the arc discharge therebetween by establishing anelectrical contact in the nature of a probe adjacent the arc andconnecting said probe through a suitable electrically controlled driveto effect movement of a movable electrode consequent upon energizationof the control circuit by contact of the probe with the arc. Theshifting of the arc in any direction from its initial point of dischargefrom a movable electrode will energize the control circuit to move theelectrode in a direction to restore the arc to its initial relativeposition between the arcing electrodes.

In the drawings, Fig. 1 illustrates an electrode assembly and associatedcontrol probes and driving mechanism; Fig. 2 is an end view of theelectrodes and associated control probes; and Fig. 3 is a side viewillustrating the preferred alignment of the electrode assembly andcontrol probes in the embodiment of Fig. 1.

Referring now to Fig. 1, there is provided an electrode assembly havinga circular or disc type electrode 1 which is mounted for rotation on adriving shaft 2 and coupled at 3 to a suitable electrical reversiblemotor enclosed in the control box. The disc electrode I is normallystationary and is rotated only for purposes of arc position control aswill be hereinafter described. In the embodiment of Fig. 1, the discelectrode I may be designated as a negative electrode, which operates inthe electrode circuit of the assembly to establish a point of arccontact between a rod type positive electrode 4 and a suitable source ofunidirectional electrical power diagrammatically represented in thecircuit. The rod type electrode 4 is mounted in a predetermined fixedrelation to the disc type electrode I and may be supported in suchposition on a suitable mounting 10.

Once the are has been established between the electrodes I and 4,optimum operation of the electrode assembly requires that the arcdischarge from the continuous negative electrode surface remain fixedrelative to the rod type electrode.

Such fixed relationship results in uniformity of are energy content andaids efficient utilization of electrode surface. In practice, it hasbeen found that in'such an arrangement the point of discharge of the archas a tendency to shift primarily because of the continuous are surfacefrom which the arc is initiated. Such are shift or displacement resultsin undesirable variations in are energy content and operation. Otherfactors that may contribute to such are displacement are the consumptionof electrode surface, variations in applied energy and electrodematerial, and variations in atmosphere in the arc area.

Such undesirable variations can be reduced in accordance with thepreferred embodiment of this invention by suitably supporting anelectricalarc conductor in the form of a probe 5 adjacent the electrodedischarge surface in spaced relation from the arc and the surface. Inthe preferred embodiment, a pair of probes are preferably positioned onopposite sides of the are as shown in Figs. 2 and 3. The probes 5 mayeach be connected electrically to a control circuit or the controlfields oilareversibleelectrical motorcthrough suitable terminals T and8, respectively, .mounted on the control box as shown in Fig. 1. Acommon return is provided for each of the probes from; the terminal 5 tothe rod electrode 4. The motor or other electrode drive is thusconnectedinan' energizing circuit through either of the-probes 5 inshunt across the normally open arc, path to.-

a particular probe. These connections are such that the circuitestablished througheither probe will energize the reversible motor inoppositeidirections. in Fig. 1 shift along the continuous-negativeelectrode surface an amount sufficient to contactthe probe circuit onthe. side of the arc shift, a control? circuit wouldjbe established?through the rod type: electrode, the. arc, and the probe con:- tacted;to. the reversible motor. The voltage-appeanlng. between thetrod;electrode and the :point in:.'the-:arcrfiametouched.by atprobeis:;applied:-to thecontrol box:at terminals! and- 8% which'aresin turnconnected to. a reversible motor-or; similar device; as hereinbeforedescribed; The motor. or diiiyesis' connected in the circuit: to beenergized tDJ-IOtfitfil the shaft" 2 andtdiscitype electrode-J in:adirectionraway'irom the probe contacted, thereby shifting the: point; ofarc;discharge out of; contact? with the probe-towards its initial'position and opening the energizing circuit. across the probeiarc'pathto'the motor. Thedisc electrode l remains stationary untilLthe arcdischarge again shirts toz'repeat: the; cycle: in either direction;

Thus, in accordance with the preferred embodiment of? this. invention,any" shifting of the point 'ofsarmdi'schargealong a continuous. negativeelectrode-- surface" will. be corrected. by movement, of *suclr' surfacein. a direction i to: maintain the point of "arc: discharge: fixed;relative;- to the other electrode. Such control serves to'maintainapredetermined or fixed: relationship-between the. position oftt'hearcrdischarge-and the. arcingelectrodes i'nr-elecrode assemblies or. thelike; The manner 'ofjenergizings the electrode control means bydirectrelectrical contact with. the displaced arcresults in. a: simple,directacting and highly sensitive control for maintainingv the'desiredare dis;- charge position.

'The: .method described herein contemplates the establishment of. adirect electrical arcxcontact. as axboun'dary to limit displacement. of.an established-arc; between arcing electrodes. Vic:- latiorr of.established. boundary conditions by; are displacement siniiici-entv tocontact. a probeboundam will. berefiected. in; a. control circuitenergized .byrsuchzcontact'to move. the electrode from: which the arcisdisplaced in; a direction tov restore: the

arc to'its initial discharge. position-and therebybrealethercontact todeenergizethe electrode moving means.

Accordingly, the principle ofthis method. may be applied to. anyelectrode arc: assembly regard,-

less' ofi form and irrespective of independent :bezthe. preferredembodiment of my invention along with suggested modified forms; and: itwill lie-obvious to. those skilled inztheart that ot'her Accordingly,should the arc discharge l changes and modifications may be made withoutdeparting from the scope of my invention as defined by the appendedclaims.

Having thus. described invention; what I claim as;- new and wish tosecureby: Letters Patent is:

1. In an arcing electrode assembly including a movable continuouselectrode surface and another electrode spaced in fixed relationtherefrom, e electrically controlled means for moving said continuouselectrode surface relative to said other electrode, an arc conductorpositioned adjacent said movable-electrode surface in spaced relation'fromthearc and said surface, and means connecting said electrode movingmeans through said arcconductor and across the normally open 'arc pathto said arc conductor, the said are conductor being adapted to becontacted by the arc torenergizasaidi moving. means consequent upondisnlacementiof the arc towardsacontact with-saidconductor'to.movextheelectrode surface in adi- .ing means-through the;arc conductor and across the. normally open arc path, the said are com.ductoribeing adapted to be contacted by the arc toenergizesaictmovingameans consequent upon displacementwf thearc towardscontact with said conductor; to. move the electrode surface in adirection'to return the displaced arc to its initial positionrelativezto the other electrode.

3;. Inanarcing electrode assembly includin a pair of electrodes arrangedfor passage of an arc therebetween, means for moving one of theelectrodes; anveiectrical control circuit for the movable-electrodehaving a point of direct electrical arc: contact positioned adjacent thenormal arc path between the said pair of electrodes andspaced-therefrom, said. point. of electrical contact adapted to; becontacted by-the. arc consequent upon. displacement of the are from itsnormal path. between the pair of electrodes and towards the saidpointrofarc contact to. energize the control circuitandmove themovable electrodein a direction to return the displaced arc to its initial normal pathbetweenthesaid pair. of electrodes.

.4. "In; an. arcing electrode assembly including a movable continuouselectrode surface, electrically controlled means "for moving saidelectrode surface in opposite. directions relative to another electrode,a pair of arc conductors, each of said conductors positioned adjacentsaid electrode surfaceinspaced relation from thearc and said.surfaceqand means connecting said electrode moving means; in: reversingrelation through. said conductors and across the normally open arc pathto each conductor. respectively, each of said are conductorsadapted, tobe contacted by the arcconsequentupon displaccmentof the arc towards therespective conductor to energize the electrode moving means and move theelectrode surfacein a. direction to return the displaced arc to itsinitial positionbetween the electrodes.

5.. Anelectrode assembly comprising in combination, a pair ofelectrodes, means for establishing an are between said electrodes,electrical means for moving one of said electrodes, the other electrodeof the pair being fixedly mounted in spaced relation to the movableelectrode, an electrical arc contact supported in spaced relationadjacent the point of arc discharge from said movable electrode to thefixedly mounted electrode, normally open circuit means connecting saidelectrical arc contact to said electrode moving means whereby saidmoving means are energized in a predetermined direction to return thearc to its initial position consequent upon arc displacementestablishing the circuit through said electrical are contact.

6. In an arcing electrode assembly, a disc type electrode, a rod typeelectrode cooperatively positioned in predetermined fixed relationrelative to said disc type electrode, electrically controlled reversiblemeans drivingly connected to said disc type electrode, a pair ofelectrical probes positioned in the plane of the disc electrode adjacentthe arc path and spaced on opposite sides therefrom respectively, meansreversibly connecting each of said probes respectively through thenormally open arc path to each probe to energize said driving means,said normally open energizing circuit adapted to be energized by the arcconsequent upon displacement of the arc towards contact with thecorresponding probe to move the electrode in a direction to return thedisplaced arc to its initial position in the electrode assen.- bly.

7. In an arcing electrode assembly having a rotatable disc typeelectrode and a rod type electrode spaced in fixed relation therefromand including electrical means to establish an arc therebetween,reversible electric driving means operably coupled to said disc typeelectrode, a pair of electrode probes each positioned on opposite sidesof the arc discharge and spaced therefrom adjacent the periphery of saiddisc type electrode, means connecting each of said probes with saidelectrical driving means across the normally open arc path to each proberespectively to effect rotation of the disc electrode in oppositedirections consequent upon displacement and contact of the arc dischargewith the corresponding probe.

8. An arcing electrode assembly comprising in combination, a disc typeelectrode, a rod type electrode suitably supported at a fixed spacingfrom said disc type electrode, electrically reversible driving meansoperably coupled to said disc type electrode, a source of power, circuitmeans con- 6 nectin said source of power between said electrodes toestablish an arc therebetween, a pair of electrode probes eachpositioned on opposite sides or" said are discharge and spaced therefromadjacent the periphery of said disc electrode, means connecting each ofsaid probes with said driving means across the normally open arc path toeach probe respectively to energize said driving means in a direction torestore the arc to its initial position consequent upon displacement andcontact of said are discharge with a corresponding probe.

9. In an arcing electrode assembly including a movable continuouselectrode surface and another electrode spaced in fixed relationtherefrom, electrically controlled means for moving said continuouselectrode surface relative to other electrode, an arc conductorpositioned adjacent said movable continuous electrode surface in spacedrelation from the arc and said surface, and normally open circuit meansconnecting said electrode moving means in circuit relation between saidare conductor and the fixed electrode across the normally open arc pathto said are conductor to energize said moving means consequent upondisplacement of the arc towards contact with said are conductor, wherebysaid continuous electrode surface is moved in a direction to restore thedisplaced arc to its initial normal path between the movable continuouselectrode surface and the fixed electrode and away from contact withsaid are conductor.

10. In an arcing electrode assembly including a movable continuouselectrode surface and another electrode spaced in predetermined relationtherefrom, electrically controlled moving means for moving saidelectrode surface in opposite directions relative to said otherelectrode, a pair of arc conductors, each of said conductors positionedadjacent said electrode surface in spaced relation from the arc and saidsurface, and means connecting said electrode moving means in reversingrelation between each conductor and said other electrode across thenormally open arc path to each conductor respectively, each of said areconductors adapted to be contacted by the arc consequent upondisplacement of the arc towards the respective conductor, whereby saidelectrode moving means is energized to move said electrode surface in adirection to return the displaced arc to its initial position betweenthe electrodes and away from contact with said conductor.

LOUIS R. NOFFSINGER.

No references cited.

